1. Field of the Invention
A push-broom for sweeping or cleaning hard horizontal surfaces.
2. Description of the Prior Art
Brooms used for sweeping or cleaning hard horizontal surfaces, e.g. wood, tile, cement, linoleum, asphalt and other uncarpeted surfaces, are available in a variety of sizes, shapes and constructions, some of which are particularly suitable for a specific cleaning task or specific type of surface. Whereas an ordinary kitchen-type broom, having an elongated handle with a tied bundle of broom straws attached at one end, with the handle and bristles oriented along the same axis of symmetry, is adequate for sweeping relatively small areas, such as are found in the home, it has been discovered that a push-broom is far more suitable for sweeping loose dirt and particles from a large surface area.
A push-broom is characterized by having an elongated handle attached to a block, almost always of wood, which is generally rectangular in plan and which has discrete bundles of bristles attached to the underside thereof, i.e. the side which faces away from the handle-block connection, much in the nature of a brush.
In the typical prior art push-broom, a blind cylindrical bore is provided in the upper surface of the broom block, i.e. the surface opposite the bristles, adjacent to one ot its longer edges. The bore is formed with a female thread for all or a part of its length and is inclined so that its axis is perpendicular to the longest axis of the rectangular block, and is at an oblique angle with respect to the plane of the upper surface of the block. The broom handle is provided at its lower end with a male thread that is shaped and dimensioned to permit the handle to be screwed into the bore and secured. Some push-broom handles are secured in a permanent fashion to the blocks by L-shaped metal straps or brackets, each of which has one leg secured to the lower end of the broom handle and the other leg secured to the upper surface of the broom block.
A push-broom is utilized by holding the upper end of the handle at an angle which will position the broom bristles on the underside of the block so that they are substantially perpendicular to the floor for maximum sweeping contact and dirt displacement, and the broom is then pushed in front of the user. Generally, the angle defined by the broom handle and the upper surface of the block is such that a person can comfortably push the broom in front of him while holding the upper end of the handle and maintain the bristles in their optimum cleaning position. The dirt and particles to be swept from the floor are then pushed in front of the user until they are displaced to a desired location where they can later be picked up and discarded.
Certain variations on the above-described conventional push-broom construction have been developed in the prior art. For example, U.S. Pat. No. 2,705,336 discloses a push-broom having a block with a substantially domed-shaped upper surface rather than a flat surface with perpendicular dependent walls. In addition, the broom disclosed in that patent has a reversible handle that is provided with a connector structure at each end, with the end to be held by the user covered by a removable cushioned cap. Moreover, the broom shown in that patent has no reinforcing metal straps or brackets but merely has at each connector end a threaded portion of somewhat reduced thickness which screws into a fully threaded bore in the broom block.
British Pat. No. 806,145 discloses a broom having a plastic (such as polyethylene) block with a protruding socket having internal ribs or serrations. The socket is sufficiently resilient to grip the end of the broom handle when it is forced into the socket, but the ribs within the socket hold the handle firmly by frictional contact. The broom handle is not threaded to any extent and can be reversed so that either end may be thrust into the resilient socket in the block.
All of the above push-broom constructions have distinct advantages both with respect to their method of manufacture and with respect to their durability and effectiveness in use. The production of the conventional push-broom construction described above, having a threaded blind bore in a wooden broom block, necessitates the carving of the bore and the threading thereof in the wooden block, which is a relatively costly and time-consuming process. Furthermore, because the length of the bore and of the threaded portion of the broom handle and because substantial force is exerted downwardly on the upper end of the broom handle by the user at an angle to the axis of the bore, the connection between the handle and the block requires reinforcement; thus, the additional manufacturing step of applying and securing the metal straps or brackets must be performed. In addition, once the brackets are secured, the broom handle can no longer be conveniently removed or replaced and the broom is normally discarded when the handle or block becomes worn or cracked.
The broom disclosed in the '336 patent, while providing for easy reversal or replacement of the broom handle, has a wooden block which must be carved, including the fashioning of the two blind threaded bores therein, and has a short, unsupported threaded connection between the handle and block which does not provide adequate strength or freedom from play. The British '145 patent does disclose a push-type broom with a plastic block, but that broom depends solely on the friction between the ribs in the resilient socket of the block and the end of the handle for the securing of the handle in the block. This type of connection is far more liable to cause axial slippage of the handle, as well as rotational slippage, than a threaded connection.